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authorAaron Durbin <adurbin@chromium.org>2013-10-04 11:17:45 -0500
committerAaron Durbin <adurbin@google.com>2014-02-05 05:24:20 +0100
commit189aa3e2aec9ca6446d8425a3ec3a11cb4b5c696 (patch)
tree15cfa428fdfa96c31715f8c2556ad7a568ff1e7b /src/soc/intel/baytrail/romstage/pmc.c
parentc0270aa6d0e183ceb04566b6e9e3939bd9215d35 (diff)
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baytrail: initialize punit
The punit is responsible for a number of things. Without performing the sequence included it won't change processor frequency when requested and apparently there are some bizarre hangs introduced if this sequence isn't included either. Lastly, this needs to come after microcode has been loaded. As that is done in bootblock the ordering is correct. One other side effect is that this fixes the graphics devices' device id. Before it was showing up as the same device id of the SoC transaction router. BUG=chrome-os-partner:22880 BUG=chrome-os-partner:23085 BUG=chrome-os-partner:22876 BRANCH=None TEST=Built and booted. Change-Id: Ib7be1d4b365e9a45647c778ee5f91de497c55bf1 Signed-off-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: https://chromium-review.googlesource.com/171862 Reviewed-by: Shawn Nematbakhsh <shawnn@chromium.org> Reviewed-on: http://review.coreboot.org/4864 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Diffstat (limited to 'src/soc/intel/baytrail/romstage/pmc.c')
-rw-r--r--src/soc/intel/baytrail/romstage/pmc.c20
1 files changed, 20 insertions, 0 deletions
diff --git a/src/soc/intel/baytrail/romstage/pmc.c b/src/soc/intel/baytrail/romstage/pmc.c
index e689ccd527a4..49a80111f53d 100644
--- a/src/soc/intel/baytrail/romstage/pmc.c
+++ b/src/soc/intel/baytrail/romstage/pmc.c
@@ -33,3 +33,23 @@ void tco_disable(void)
reg |= TCO_TMR_HALT;
outl(reg, ACPI_BASE_ADDRESS + TCO1_CNT);
}
+
+/* This sequence signals the PUNIT to start running. */
+void punit_init(void)
+{
+ uint32_t reg;
+
+ /* Write bits 17:16 of SB_BIOS_CONFIG in the PUNIT. */
+ reg = SB_BIOS_CONFIG_PERF_MODE | SB_BIOS_CONFIG_PDM_MODE;
+ pci_write_config32(IOSF_PCI_DEV, MDR_REG, reg);
+ reg = IOSF_OPCODE(IOSF_OP_WRITE_PMC) | IOSF_PORT(IOSF_PORT_PMC) |
+ IOSF_REG(SB_BIOS_CONFIG) | IOSF_BYTE_EN_2;
+ pci_write_config32(IOSF_PCI_DEV, MCR_REG, reg);
+
+ /* Write bits 1:0 of BIOS_RESET_CPL in the PUNIT. */
+ reg = BIOS_RESET_CPL_ALL_DONE | BIOS_RESET_CPL_RESET_DONE;
+ pci_write_config32(IOSF_PCI_DEV, MDR_REG, reg);
+ reg = IOSF_OPCODE(IOSF_OP_WRITE_PMC) | IOSF_PORT(IOSF_PORT_PMC) |
+ IOSF_REG(BIOS_RESET_CPL) | IOSF_BYTE_EN_0;
+ pci_write_config32(IOSF_PCI_DEV, MCR_REG, reg);
+}